This application relates to graft fixation, and more particularly to graft tissue fixation employing flipping-type fixation devices.
Flipping-type fixation devices, such as disclosed in U.S. Pat. Nos. 5,306,301 and 5,645,588 incorporated herein by reference, allow a simple procedure to be used for fixing tissue such as in an Anterior Cruciate Ligament (ACL) reconstruction. Such device comprises an elongated bar having a central suture loop depending therefrom. A tunnel is prepared in the femur from a position at or near the patellar surface up through a portion of the femur and exiting through the side of the femur at a superior location. A graft is looped over the loop attached to the elongated bar. The bar is able to pass in one direction up through the tunnel. After exiting the superior end of the tunnel, the bar is flipped approximately 90 degrees so that it will not pass back through the tunnel and is positioned against the femur with the loop and graft hanging down into the tunnel therefrom. Tension on the graft keeps the bar in place against the bone surface.
To initiate the flipping, however, the bar must be passed completely outside of the tunnel. When it is then placed down against the bone the suture loop falls back into the tunnel by the amount that it was pulled free of the tunnel, about 50% of the length of the bar. This decreases the contact of the graft with the bone in the tunnel. Also, longer loop lengths have the potential to increase motion of the graft within the tunnel, thus potentially slowing the healing process in which the graft attaches to the bone.